PageCache 2.0 Beta 1 has been released!  While it has been tested both by myself, and a handful of private testers, I do not recomend using it on a live site.  So, whats new in 2.0 you ask?  I ask what isn't new!  The entire component was rewritten from the ground up.  PageCache 2.0 shares maybe around 30 lines of code (out of more than 4,000) with 1.0.  To go into every new feature would take forever, so I'll just hit the major points (the one's you'll be most interested in reading). 

• More flexable storage system (not only are there more storage types available, but you can easially write and install your own).
• More flexable statistics system (you can choose between file and database, or write your own if you are so inclined).
• More flexable backend language system (the component will choose a language based upon the Joomla default language ($mosConfig_lang).  If there isn't a language that matches, it'll pick from the default configured in the backend.  To install a language, just copy the file into the /administrator/components/com_pagecache/languages directory.  It'll automatically recognize it and install it.
• An upgrader (you no longer need to uninstall the component to upgrade.  Just click "Upgrade")
• Support for Cron based refresh (included is a cron script).  See the FAQ item PageCache 2.0 Supports Cron for more information
• Very flexable module system.  This system is based off of "triggers" at certain points in the funcionality of the component.  Included is an installer to install custom modules.  See the FAQ item I Want To Create A Module for more information.
• The ability to run without a single SQL query (on the front end).  The component includes file based modules, so you can configure it to either use the database, or use files.  Exclusivly.
• "Clear Cache" module included and installed by default (published next to the logout button by defult) for the Administration section. 
• "Cached Pages" section now shows all pages (not just those in the cache).  Cached items are identified by the "Time To Live" section.  The entire result list is sortable by every column, and you can filter the results by part of the page name.  It also computes the average load time for cached pages, uncached pages, and disable pages.  It also displays the total hits.